<template>
  <!-- 头部部分 -->
  <header class="header">
    <h1>todos</h1>
    <!-- .trim 取出首尾的空白字符 -->
    <input @keydown.enter="hAdd" v-model.trim="taskname" class="new-todo" placeholder="请输入任务名称" autofocus />
  </header>
</template>

<script>
export default {
  data() {
    return {
      taskname: ''
    }
  },
  methods: {
    hAdd() {
      if (this.taskname === '') return alert('内容不能为空')
      this.$emit('addTask', this.taskname)
      this.taskname = ''
    }
  }
}
</script>

<style>

</style>